Hello all.. I recently convinced myself that a digital crossover like the minidsp will outperform any active analog crossover and at the same time I also convinced myself that a diy dac like the buffalo III with Legato 3.1 I/V stage will be just about as good as any dac gets.. Well certainly better than my Audio alchemy XDP/DTI anyway.
Please correct me if i'm way off so far!!

So now i'm considering buying all this stuff, but I dont want to use the oneboard dac in the minidsp and likewise I dont want to use the digital volume.. This is what I had in mind:

cd player spdif out => minidsp (2 way crossover) => Buffalo dac => preamp/step attenuator => and the rest is no surprise!

How do I go about doing this?
How do I make the minidsp spit out 2 crossed digital signals - one for bass and one for treble?
Will I be needing 4 Buffalo's and 4 Legato's?
Is it possible to buy a 4 way step attenuator as a volume control? Or how do I manage analog attenuation of 4 seperate signals?